I propose that the distinction between illegal and irregular UTF-8
code sequences (D36bc) be eliminated. Since there are no code points
between U+D7FF and U+E000 (the apparently intervening code points
are UTF-16 code units, but not Unicode code points)
the corresponding UTF-8 code sequences should be illegal.

This can be achieved by replacing the U+1000..U+FFFF row in
Table 3.1B as follows: